Luo Xing, Tuan Tong Hoang, Saini Than Singh, Nguyen Hoa Phuoc Trung, Suzuki Takenobu, Ohishi Yasutake
Opt Express. 2019 May 13;27(10):14635-14647. doi: 10.1364/OE.27.014635.
Mode-locked fiber lasers that generate two frequency combs with different frequency intervals could find very important applications in low-complexity dual-comb metrology. We report a partially polarization-maintaining all-fiber dual-wavelength dual-comb mode locked laser. The polarization dependent loss of the wavelength division multiplexer combined with the polarization-maintaining fibers leads to the periodic Lyot filtering effect. Traditional single wavelength mode locking can be realized with the tunable central wavelength and spectral shape. By properly setting the state of the polarization controller, stable dual-wavelength asynchronized mode locked pulse trains with the repetition rate difference of hundreds of Hertz can be achieved. In this dual-wavelength mode locked fiber laser, the dispersion of the laser cavity leads to group velocity difference of the two mode locked pulse trains with different central wavelengths, which results in the generation of dual-comb output with the frequency difference of hundreds of Hertz. The central wavelengths of the dual-wavelength mode locked fiber laser are demonstrated to be tunable in a certain range as well. Meanwhile, a novel dual-wavelength soliton molecule mode locking is also demonstrated. Such compact all-fiber dual-wavelength dual-comb mode locked laser could find various practical applications that in need of dual-comb fiber laser system.
能产生具有不同频率间隔的两个频率梳的锁模光纤激光器在低复杂度双梳计量学中可找到非常重要的应用。我们报道了一种部分保偏全光纤双波长双梳锁模激光器。波分复用器与保偏光纤相结合的偏振相关损耗会导致周期性的利奥滤光效应。利用可调谐中心波长和光谱形状可实现传统的单波长锁模。通过适当设置偏振控制器的状态，可实现重复频率差为数百赫兹的稳定双波长非同步锁模脉冲序列。在这种双波长锁模光纤激光器中，激光腔的色散导致具有不同中心波长的两个锁模脉冲序列的群速度不同，从而产生频率差为数百赫兹的双梳输出。双波长锁模光纤激光器的中心波长也被证明在一定范围内是可调谐的。同时，还展示了一种新型的双波长孤子分子锁模。这种紧凑的全光纤双波长双梳锁模激光器可在需要双梳光纤激光系统的各种实际应用中找到用武之地。
